The effect of temperature on the efficiency of industrial wastewater nitrification and its (geno)toxicity

Abstract

Abstract:The paper deals with the problem of the determination of the effects of temperature on the effi ciency of the nitrifi cation process of industrial wastewater, as well as its toxicity to the test organisms. The study on nitrifi cation effi ciency was performed using wastewater from one of Polish chemical factories. The chemical factory produces nitrogen fertilizers and various chemicals. The investigated wastewater was taken from the infl uent to the industrial mechanical-biological wastewater treatment plant (WWTP). The WWTP guaranteed high removal effi ciency of organic compounds defi ned as chemical oxygen demand (COD) but periodical failure of nitrifi cation performance was noted in last years of the WWTP operation. The research aim was to establish the cause of recurring failures of nitrifi cation process in the above mentioned WWTP. The tested wastewater was not acutely toxic to activated sludge microorganisms. However, the wastewater was genotoxic to activated sludge microorganisms and the genotoxicity was greater in winter than in spring time. Analysis of almost 3 years' period of the WWTP operation data and laboratory batch tests showed that activated sludge from the WWTP under study is very sensitive to temperature changes and the nitrifi cation effi ciency collapses rapidly under 16°C. Additionally, it was calculated that in order to provide the stable nitrifi cation, in winter period the sludge age (SRT) in the WWTP should be higher than 35 days.

Disentangling the Drivers of Diversity and Distribution of Fungal Community Composition in Wastewater Treatment Plants Across Spatial Scales

“…Temperature had significant influence on fungal communities associated with JJ, GZ, TJ2, and LZ1 ( Figure 7 ). Temperature, an important physical parameter, can significantly affect the microbial community in WWTPs, the wastewater treatment efficiency ( Gnida et al, 2016 ). In this study, temperature had significant influence on structure of fungal community ( Figure 7 ).…”

Composition and Dynamics of the Activated Sludge Microbiome during Seasonal Nitrification Failure

“…This might indicate that systems operating with prolonged retention times are less affected by temperature fluctuations 9 , 12 . However, other laboratory studies using reactors operated similarly to full-scale sequencing batch reactors (SRBs) have reported a direct correlation between loss of nitrifying biomass and decreasing nitrogen removal efficiency 13 – 18 . Still other laboratory studies have observed a decrease of ammonia removal efficiency at lower temperatures with no decrease in the abundance of ammonia-oxidizing bacteria, but notable fluctuations in the abundance of nitrite-oxidizing bacteria 19 – 21 .…”

Microbial ecology of full-scale wastewater treatment systems in the Polar Arctic Circle: Archaea, Bacteria and Fungi

“…It has been found that temperature is a parameter that greatly affects microbial community diversity and structure in WWT plants 11 . Cold temperature has been reported to affect microbial growth due to decrease in water availability, molecular motion and energetics, and increase in solute concentration due to decrease in water availability 12 , 13 . However, the adaptation of microbial communities to low temperature has been found to be problematic for WWT systems.…”